DESCRIPTION OF TROCHOPTERIS. 75 
reticulata, e vertice ad medium annulata, radiatim striata, 
extrorsum longitudinaliter dehiscentia. Sporwle triangulares, 
striate, sub lente minutissimé scabrelle. 
Nomen ex rpoxos rota et xrepic filix, dispositionem frondis 
indicans. 
This curious and elegant little fern belongs to the tribe 
Schizeacee, to all the genera of which it is very closely 
related; but to Anemia it bears the greatest affinity, and, 
indeed, it can only be distinguished by its very different 
habit. Its peculiarity in this respect is, however, I conceive 
quite sufficient to constitute it as good a genus as many which 
have lately been established in the now extensive family to 
which it belongs. In Anemia there are always two kinds of 
fronds—the barren and the fertile. These either arise dis- 
tinetly and separately from the rhizoma, as in A. aurita, 
W., my two new species above referred to, and others be- 
longing to the same division ; or a union of the stipes of two 
fertile fronds with a barren one takes place, as in those species 
which appear to have their fertile spikes formed from the 
lower leaflets of a barren frond. That such is the correct 
view of the manner in which fructification takes place in 
Anemia, and not that the sporangia are produced upon a 
changed portion of the frond, as Endlicher and others suppose, 
Is, I think confirmed by the fact of the fertile fronds some- 
times arising separately from the rhizoma, and not differing 
in general appearance from the barren ones; and this is made 
more evident when we sometimes find the lower half only of 
the spike bearing sporangia, the upper being a perfect fac- 
simile of the same portion of the barren fronds. Again, in 
the other division of the genus, such as in .4. Mandioccana, 
Raddi, we find the two fertile spikes placed opposite to each 
other, which would not be the case were they modified leaf- 
lets, for these are always alternate. 
In Trochopteris the fructification is produced in a very dif- 
ferent manner. In it there is only one kind of frond—a 
simple one, generally divided into five lobes, the two lower of 
Which always bear the s porangia upon their lacerated margins; 
a 2 
